This invention relates to fluid filters and more particularly to a hydraulic fluid filter having a differential pressure indicator.
Hydraulics filters of this type are commonly used as suction line filters, return line filters and pressure filters as well as in other configurations and it is conventional to employ specific designs of the filter housing for each of such applications.
In all these arrangements it is necessary from time to time to replace the filter element and it is often desired to accomplish such changeover without shutdown of the associated fluid system. Further, each filter design must be efficient in structure not only to achieve the results of adequate removal of particles of a particular size from the system but also to achieve sufficient dirt capacity in a convenient housing structure along with a favorable fluid flow versus pressure drop characteristic.
Still further in fluid filters of this type it is desirable to have means for monitoring the condition of the filter element to determine when the latter has become contaminated and requires replacement.
It would be desirable to have a common filter structure which is suitable for use in many of these different applications, wherein servicing of the filter element may be accommodated through either end of the filter housing or even from the central portion thereof and wherein the typical filter characteristics of quality of filtering are not sacrificed. Further it is desirable as well to provide means for indicating not only the condition of the filter element but also the presence or absence of same in the filter housing, with such indication provided either at the filter housing or at a remote location.